In our current protocol (IRB #2000/0024) the immunosuppressive regimen, comprised of induction with daclizumab and maintenance therapy with sirolimus and tacrolimus, has been combined with the infusion of CD34+ enriched donor bone marrow stem cells in an attempt to create a chimeric state and hence induce donor tolerance. This strategy was tested by evaluating graft survival following the removal of all immunosuppressive medication after one year.